Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 237 insertions, 0 deletions

diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c
new file mode 100644
index 000000000..9880247a2
--- /dev/null
+++ b/tools/perf/util/comm.c
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "comm.h"
+#include <errno.h>
+#include <string.h>
+#include <internal/rc_check.h>
+#include <linux/refcount.h>
+#include <linux/zalloc.h>
+#include <tools/libc_compat.h> // reallocarray
+
+#include "rwsem.h"
+
+DECLARE_RC_STRUCT(comm_str) {
+	refcount_t refcnt;
+	char str[];
+};
+
+static struct comm_strs {
+	struct rw_semaphore lock;
+	struct comm_str **strs;
+	int num_strs;
+	int capacity;
+} _comm_strs;
+
+static void comm_strs__remove_if_last(struct comm_str *cs);
+
+static void comm_strs__init(void)
+	NO_THREAD_SAFETY_ANALYSIS /* Inherently single threaded due to pthread_once. */
+{
+	init_rwsem(&_comm_strs.lock);
+	_comm_strs.capacity = 16;
+	_comm_strs.num_strs = 0;
+	_comm_strs.strs = calloc(16, sizeof(*_comm_strs.strs));
+}
+
+static struct comm_strs *comm_strs__get(void)
+{
+	static pthread_once_t comm_strs_type_once = PTHREAD_ONCE_INIT;
+
+	pthread_once(&comm_strs_type_once, comm_strs__init);
+
+	return &_comm_strs;
+}
+
+static refcount_t *comm_str__refcnt(struct comm_str *cs)
+{
+	return &RC_CHK_ACCESS(cs)->refcnt;
+}
+
+static const char *comm_str__str(const struct comm_str *cs)
+{
+	return &RC_CHK_ACCESS(cs)->str[0];
+}
+
+static struct comm_str *comm_str__get(struct comm_str *cs)
+{
+	struct comm_str *result;
+
+	if (RC_CHK_GET(result, cs))
+		refcount_inc_not_zero(comm_str__refcnt(cs));
+
+	return result;
+}
+
+static void comm_str__put(struct comm_str *cs)
+{
+	if (!cs)
+		return;
+
+	if (refcount_dec_and_test(comm_str__refcnt(cs))) {
+		RC_CHK_FREE(cs);
+	} else {
+		if (refcount_read(comm_str__refcnt(cs)) == 1)
+			comm_strs__remove_if_last(cs);
+
+		RC_CHK_PUT(cs);
+	}
+}
+
+static struct comm_str *comm_str__new(const char *str)
+{
+	struct comm_str *result = NULL;
+	RC_STRUCT(comm_str) *cs;
+
+	cs = malloc(sizeof(*cs) + strlen(str) + 1);
+	if (ADD_RC_CHK(result, cs)) {
+		refcount_set(comm_str__refcnt(result), 1);
+		strcpy(&cs->str[0], str);
+	}
+	return result;
+}
+
+static int comm_str__search(const void *_key, const void *_member)
+{
+	const char *key = _key;
+	const struct comm_str *member = *(const struct comm_str * const *)_member;
+
+	return strcmp(key, comm_str__str(member));
+}
+
+static void comm_strs__remove_if_last(struct comm_str *cs)
+{
+	struct comm_strs *comm_strs = comm_strs__get();
+
+	down_write(&comm_strs->lock);
+	/*
+	 * Are there only references from the array, if so remove the array
+	 * reference under the write lock so that we don't race with findnew.
+	 */
+	if (refcount_read(comm_str__refcnt(cs)) == 1) {
+		struct comm_str **entry;
+
+		entry = bsearch(comm_str__str(cs), comm_strs->strs, comm_strs->num_strs,
+				sizeof(struct comm_str *), comm_str__search);
+		comm_str__put(*entry);
+		for (int i = entry - comm_strs->strs; i < comm_strs->num_strs - 1; i++)
+			comm_strs->strs[i] = comm_strs->strs[i + 1];
+		comm_strs->num_strs--;
+	}
+	up_write(&comm_strs->lock);
+}
+
+static struct comm_str *__comm_strs__find(struct comm_strs *comm_strs, const char *str)
+	SHARED_LOCKS_REQUIRED(comm_strs->lock)
+{
+	struct comm_str **result;
+
+	result = bsearch(str, comm_strs->strs, comm_strs->num_strs, sizeof(struct comm_str *),
+			 comm_str__search);
+
+	if (!result)
+		return NULL;
+
+	return comm_str__get(*result);
+}
+
+static struct comm_str *comm_strs__findnew(const char *str)
+{
+	struct comm_strs *comm_strs = comm_strs__get();
+	struct comm_str *result;
+
+	if (!comm_strs)
+		return NULL;
+
+	down_read(&comm_strs->lock);
+	result = __comm_strs__find(comm_strs, str);
+	up_read(&comm_strs->lock);
+	if (result)
+		return result;
+
+	down_write(&comm_strs->lock);
+	result = __comm_strs__find(comm_strs, str);
+	if (!result) {
+		if (comm_strs->num_strs == comm_strs->capacity) {
+			struct comm_str **tmp;
+
+			tmp = reallocarray(comm_strs->strs,
+					   comm_strs->capacity + 16,
+					   sizeof(*comm_strs->strs));
+			if (!tmp) {
+				up_write(&comm_strs->lock);
+				return NULL;
+			}
+			comm_strs->strs = tmp;
+			comm_strs->capacity += 16;
+		}
+		result = comm_str__new(str);
+		if (result) {
+			int low = 0, high = comm_strs->num_strs - 1;
+			int insert = comm_strs->num_strs; /* Default to inserting at the end. */
+
+			while (low <= high) {
+				int mid = low + (high - low) / 2;
+				int cmp = strcmp(comm_str__str(comm_strs->strs[mid]), str);
+
+				if (cmp < 0) {
+					low = mid + 1;
+				} else {
+					high = mid - 1;
+					insert = mid;
+				}
+			}
+			memmove(&comm_strs->strs[insert + 1], &comm_strs->strs[insert],
+				(comm_strs->num_strs - insert) * sizeof(struct comm_str *));
+			comm_strs->num_strs++;
+			comm_strs->strs[insert] = result;
+		}
+	}
+	up_write(&comm_strs->lock);
+	return comm_str__get(result);
+}
+
+struct comm *comm__new(const char *str, u64 timestamp, bool exec)
+{
+	struct comm *comm = zalloc(sizeof(*comm));
+
+	if (!comm)
+		return NULL;
+
+	comm->start = timestamp;
+	comm->exec = exec;
+
+	comm->comm_str = comm_strs__findnew(str);
+	if (!comm->comm_str) {
+		free(comm);
+		return NULL;
+	}
+
+	return comm;
+}
+
+int comm__override(struct comm *comm, const char *str, u64 timestamp, bool exec)
+{
+	struct comm_str *new, *old = comm->comm_str;
+
+	new = comm_strs__findnew(str);
+	if (!new)
+		return -ENOMEM;
+
+	comm_str__put(old);
+	comm->comm_str = new;
+	comm->start = timestamp;
+	if (exec)
+		comm->exec = true;
+
+	return 0;
+}
+
+void comm__free(struct comm *comm)
+{
+	comm_str__put(comm->comm_str);
+	free(comm);
+}
+
+const char *comm__str(const struct comm *comm)
+{
+	return comm_str__str(comm->comm_str);
+}